Ipswitch IMail IMAP STATUS Remote Buffer Overflow Vulnerability iDEFENSE Security Advisory 05.24.05 www.idefense.com/application/poi/display?id=244&type=vulnerabilities May 24, 2005 I. BACKGROUND Ipswitch Collaboration Suite (ICS) is a comprehensive communication and collaboration solution for Microsoft Windows with a customer base of over 53 million users. More information is available on the vendor's website: http://www.ipswitch.com/products/IMail_Server/index.html II. DESCRIPTION Remote exploitation of a buffer overflow vulnerability in Ipswitch Inc.'s Imail IMAP server allows attackers to execute arbitrary code with System privileges. The vulnerability specifically exists in the handling of a long mailbox name to the STATUS command. A long mailbox name argument will cause a stack based buffer overflow, providing the attacker with full control over the saved return address on the stack. Once this has been achieved, execution of arbitrary code becomes trivial. As this vulnerability is in the STATUS command, which requires that a session is authenticated, valid credentials are required. III. ANALYSIS Successful exploitation allows remote attackers to execute arbitrary code with System privileges. Valid credentials are required for exploitation, which lessens the impact of this vulnerability. IV. DETECTION iDEFENSE has confirmed the existence of this vulnerability in Ipswitch IMail version 8.13. It is suspected that earlier versions are also vulnerable. V. WORKAROUND As this vulnerability is exploited after authentication occurs, ensuring that only trusted users have accounts can mitigate the risk somwhat. As a more effective workaround, consider limiting access to the IMAP server by filtering TCP port 143. If possible, consider disabling IMAP and forcing users to use POP3. VI. VENDOR RESPONSE The vendor has released the following patch to fix this vulnerability: ftp://ftp.ipswitch.com/Ipswitch/Product_Support/IMail/imail82hf2.exe The associated vendor advisory can be found at: http://www.ipswitch.com/support/imail/releases/imail_professional/im82hf 2.html VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CAN-2005-1256 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems. VIII. DISCLOSURE TIMELINE 04/25/2005 Initial vendor notification 05/10/2005 Initial vendor response 05/24/2005 Public disclosure IX. CREDIT iDEFENSE Labs is credited with this discovery. Get paid for vulnerability research http://www.idefense.com/poi/teams/vcp.jsp Free tools, research and upcoming events http://labs.idefense.com X. LEGAL NOTICES Copyright (c) 2005 iDEFENSE, Inc. Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDEFENSE. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please email customerservice@idefense.com for permission. Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/